To analyze the given data set $1.8, 1.9, 1.9, 2.0, 2.1, 2.3, 2.4, 2.5, 2.5, 2.5, 2.7, 2.8, 2.8, 2.9, 3.0, 3.2, 3.2, 3.3, 3.7, 3.8$, let's calculate the mean, median, mode, sample variance, and standard deviation.

1. Mean

The mean is calculated by summing all the values and dividing by the number of values.

$\text{Mean} = \frac{\sum \text{values}}{n}$

$\text{Mean} = \frac{1.8 + 1.9 + 1.9 + 2.0 + 2.1 + 2.3 + 2.4 + 2.5 + 2.5 + 2.5 + 2.7 + 2.8 + 2.8 + 2.9 + 3.0 + 3.2 + 3.2 + 3.3 + 3.7 + 3.8}{20} = \frac{57.5}{20} = 2.875$

2. Median

The median is the middle value when the data set is ordered. For an even number of observations, it is the average of the two middle values.

Sorted dataTo analyze the given data set $1.8, 1.9, 1.9, 2.0, 2.1, 2.3, 2.4, 2.5, 2.5, 2.5, 2.7, 2.8, 2.8, 2.9, 3.0, 3.2, 3.2, 3.3, 3.7, 3.8$, let's calculate the mean, median, mode, sample variance, and standard deviation.

1. Mean

The mean is calculated by summing all the values and dividing by the number of values.

$\text{Mean} = \frac{\sum \text{values}}{n}$

$\text{Mean} = \frac{1.8 + 1.9 + 1.9 + 2.0 + 2.1 + 2.3 + 2.4 + 2.5 + 2.5 + 2.5 + 2.7 + 2.8 + 2.8 + 2.9 + 3.0 + 3.2 + 3.2 + 3.3 + 3.7 + 3.8}{20} = \frac{57.5}{20} = 2.875$

2. Median

The median is the middle value when the data set is ordered. For an even number of observations, it is the average of the two middle values.

Sorted ( 1.8, 1.9, 1.9, 2.0, 2.1, 2.3, 2.4, 2.5, 2.5, 2.5, 2.7, 2.8, 2.8, 2.9, 3.0